Stereoscopic

Stereoscopic refers to the perception or representation of depth by presenting two slightly different images to the left and right eyes. The brain fuses the two images into a single three-dimensional scene through binocular disparity, the small horizontal differences that arise from the separation of the eyes and the angle of gaze. Stereoscopic imaging is used in photography, film, display technology, and scientific visualization to convey depth.

Historically, the concept was demonstrated in the 19th century by Charles Wheatstone, who developed the stereoscope in 1838. Since then, many methods have produced stereo pairs, including color-anaglyphs viewed with red‑cyan glasses, polarized-light systems for passive 3D cinema, and active shutter glasses that alternately block each eye. More recently, autostereoscopic displays attempt to render 3D images without glasses using lenticular or parallax-barrier designs. In digital media, stereo pairs are commonplace in 3D animation, virtual reality, and certain medical imaging workflows.

Applications include entertainment (3D movies and games), photography and reproduction of artwork, education and scientific visualization, and medical imaging where stereoscopic views aid in assessing anatomical structures. However, stereoscopic viewing can cause eye strain or headaches for some users, and a portion of the population is stereoblind and cannot perceive depth from binocular disparity. The term “stereoscopic” thus covers both the techniques for creating depth-rich imagery and the perceptual experience it aims to evoke.